1. Field of the Invention
The present invention relates to an illuminant device, and especially to an illuminant device using light emitting diode as light source.
2. Description of Prior Art
Light emitting diodes (LEDs) have the advantages of small volume, long lifetime, difficulty damage, without mercury and lower power consumption. They are gradually replacing the fluorescent tubes and incandescent lamps and widely used in indoor and outdoor lighting and decorative lighting.
Reference is made to FIG. 1, which is a sectional view of a conventional LED lamp. The LED lamp 50 includes a housing 510, a first circuit board 520, a plurality of LEDs 530, a conductive connector 540, a lamp shade 550 and a controlling and driving module 560. The housing 510 has an accommodating space 512 and a plurality of fins 514 disposed around the accommodating space 512 and used for enhancing heat-dissipating effect.
The first circuit board 520 is disposed at one end of the housing 510. The LEDs 530 are placed on the first circuit board 520 and electrically connected thereto. The conductive connector 540 is connected to the other end of the housing 510 which is opposite to where the first circuit board 520 is disposed. The lamp shade 550 is disposed in front of the LEDs 530 such that the LEDs 530 are arranged between the lamp shade 550 and the housing 510.
The controlling and driving module 560, which includes a second circuit board 562 and a plurality of electrical elements 564, is located within the accommodating space 512. The electrical elements 564 are placed on the second circuit board 562 and collectively constructing power modulating circuit and controlling circuit. The controlling and driving module 560 is electrically connected to the first circuit board 520 via multiple wires 570, and electrically connected to the conductive connector 540 via multiple power lines 580.
In the practical application, the first circuit board 520 for mounting the LEDs 530 and the second circuit board 562 for mounting the electrical elements 564 are respectively assembled with the housing 510, and then the first circuit board 520 and the second circuit board 562 are electrically connected via the wires 570. However, the manufacturing procedures of assembling the LED lamp 50 are complicated and manufacturing time is longer.
In addition, the second circuit board 562 and the electrical elements 564 of the controlling and driving module 560 have predestinated volume, such that the volume of the accommodating space 512 cannot be reduced, and the volume of the housing 510 can also not be effectively reduced.